The capability to provide multiple functions for a single device provides convenient savings in physical space and costs. One traditionally single-tasked device is an antenna. Antennas used in the communication of electromagnetic signals have been developed with a concern for size reduction while providing high fidelity information during transmission and/or reception. Patch antennas have been a preferred choice of radio frequency (RF) front end design for their reliability and low profile topology. Such a profile makes them ideal for wireless systems where physical space on a wireless device is limited. Patch antennas are also lightweight and enable mounting onto various surfaces that are not suitable for dipole, wire loop, or multi-element antennas. The patch antenna has proven to be quite effective for a variety of applications, including terrestrial and satellite communications systems and various electromagnetic scanning arrays due to its low-profile, planar structure, reasonable bandwidth, and excellent gain.
Antenna material composition is crucial in ensuring the efficient and accurate transmission and/or reception of wireless signals. The conductivity of these materials plays a critical role in not contributing to attenuation or distortion of signals already degraded by environmental factors experienced during propagation. Traditional patch antennas are constructed from conductive metals such as copper.
FIG. 1 is a schematic illustration of a traditional microstrip patch antenna. FIG. 1 depicts a patch antenna 100 mounted on a substrate 115. An electromagnetic wave is transmitted and/or received according to a radiating edge or slots (shown as 125, 130) of the patch antenna 100 given its length 105 and width 110. Radiating slots 125 and 130 produce a broadside radiation pattern 145. When the substrate thickness 140 is small, radiation is approximated by horizontal magnetic currents circulating the perimeter of the patch antenna 100 over a ground plane 135. Communication of signals received or to be transmitted by the patch antenna 100 is achieved using an impedance matched microstrip feed line 120.
Military personnel and first responders carry various equipment to communicate with others and provide environmental information about their surroundings. For example, personnel may carry a wireless communications device as well as an environmental condition detector (e.g. temperature, pressure, gas, and the like). Carrying numerous devices decreases mobility, agility, and effectiveness of the user.
Thus, there is a need in the art for a method and apparatus that can provide a multifunction sensor (e.g. both wireless communication as well as gas detection) in a compact lightweight form factor.